Empire Squad

The core is Thrawn, ShT, DT. There are several interesting leaders like Thrawn, Tarkin, Saxon which don't lead to the same strategy (speed based, counter, TM manipulation).

I've played zVeers, ShT, StormT, DT, Thrawn. Good offense and synergy.
I switched to zTarkin for the speed bonus for Thrawn too. Tarkin is a great leader imo. I've zeta'd his lead and the expose is really good even if it's not a game changer.
With better mods, I think I would switched to a Thrawn lead (offense, TM gain, protection bonus) with troopers and zVeers.

In every composition, I've let ShT, DT and Thrawn because they bring a lot to the team.

I agree, the core of any good Empire team is Thrawn, Death Trooper and Shore Trooper. I rotate Tarkin, Krennic, Veers and Snow Trooper to round them out, depending on what I'm using them for. Veers is great with the troopers because they benefit from his unique, which means you can use them with any Empire leader.

I have to say, at the moment I think Empire is the most exciting and versatile faction in the game.

Looks like I have some work to do as only Vader, EP, TFP and RG really viable right now Empire wise